Andromeda Blue Survival Mode feedback needed

Hello!
We just finished the update 1.5 and added a new game mode.
Survival is about fighting waves after waves of enemies and get as many points as possible.
It's quite a big move away from the team strategy of the original design and we haven't really got any user testing for it. The balance is off but we hope it's a step in the right direction.
So all criticism would help us tweak it further.